Memory Watched as It Forms

Creating long-term memories means chemically altering the brain. Neuroscientists at Harvard University were recently able to observe, for the first time, new protein being synthesized at the synapses between neurons (red regions in image). The synthesis was observed in fruit flies and occurred as the flies learned to associate an odor with an electric shock. Molecular biologist Sam Kunes said his team “found a new biochemical pathway that determines if and where this protein synthesis happens.”

Using fluorescent markers, Kunes could see synapses modified after exposure to the odor. The altered synapse (represented in green) meant the difference between remembering something for an hour —a short-term memory —and a day, which is long-term for a fruit fly. Because the basic structure of this biochemical pathway is the same in mice and humans, Kunes believes these findings will lead to a better understanding of how memory works in higher animals —and could eventually result in therapies to bolster fading recall.